Disrupted network interactions serve as a neural marker of dyslexia

Dyslexia, a frequent learning disorder, is characterized by severe impairments in reading and writing and hypoactivation in reading regions in the left hemisphere. Despite decades of research, it remains unclear to date if observed behavioural deficits are caused by aberrant network interactions during reading and whether differences in functional activation and connectivity are directly related to reading performance. Here we provide a comprehensive characterization of reading-related brain connectivity in adults with and without dyslexia. We find disrupted functional coupling between hypoactive reading regions, especially between the left temporo-parietal and occipito-temporal cortices, and an extensive functional disruption of the right cerebellum in adults with dyslexia. Network analyses suggest that individuals with dyslexia process written stimuli via a dorsal decoding route and show stronger reading-related interaction with the right cerebellum. Moreover, increased connectivity within networks is linked to worse reading performance in dyslexia. Collectively, our results provide strong evidence for aberrant task-related connectivity as a neural marker for dyslexia that directly impacts behavioural performance. The observed differences in activation and connectivity suggest that one effective way to alleviate reading problems in dyslexia is through modulating interactions within the reading network with neurostimulation methods.


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All manuscripts must include a data availability statement.This statement should provide the following information, where applicable: -Accession codes, unique identifiers, or web links for publicly available datasets -A description of any restrictions on data availability -For clinical datasets or third party data, please ensure that the statement adheres to our policy Data and code underlying all analyses and figures is provided via the following OSF registry: https://osf.io/cy8tk/113 (no password needed).The hypoactive areas from the univariate analyses were taken as ROIs and we compared activation for all four conditions (simple words, complex words, simple pseudowords and complex pseudowords) in the two groups
Provide a description of all commercial, open source and custom code used to collect the data in this study, specifying the version used OR state that no software was used.https://osf.io/cy8tk/natureportfolio | reporting summaryIn-scanner performance measures: speech onsets, reading times, accuracy for all four conditions (simple words, complex words, simple pseudowords, complex pseudowords).Correltaions with out-of-scanner performance measures: speeded word and pseudoword reading (SLRT-II), text reading speech, accuracy and comprehension (LGVT 5-12+), spelling and phonological processing (spelling test, phoneme substitution task), verbal working memory (digit span forward and backward, nonword span), nonverbal IQ, arithmetic skills and continuous attention test